We will update the power rankings each week during the regular season and release the final rankings for the season after the BCS title game.

The rating of a player and coach can fluctuate each week during the season depending on how they fared the previous week, but the power rankings measure overall career performances as well as their most recent results.

Here are the nation's top 20 safeties. Next up: special teamers.

SAFETY POWER RANKINGS

1. FS Rahim Moore, UCLA (6-1/196, Jr.)BUZZ: Free safeties are supposed to be playmakers, and Moore certainly fits that mold. Moore led the nation in interceptions last season with 10, giving him 13 picks in his two-year career. He got his interceptions in bunches, with multiple picks in games against San Diego State, Tennessee and Arizona. He also made 49 tackles and has seven pass breakups.

2. SS DeAndre McDaniel, Clemson (6-1/210, Sr.)BUZZ: A big hitter, McDaniel made 98 tackles and had eight interceptions last season. He scored on a 24-yard interception return in Clemson's OT victory over Miami. He has 199 tackles and 11 picks in his career.

3. FS Tejay Johnson, TCU (6-1/212, Sr.)BUZZ: Johnson is heading into his third season as a starter for the defense-minded Horned Frogs; he had 59 tackles and three picks last season, and he showed a flair for delivering big performances in big games. Johnson made 14 tackles -- the highest single-game total by any TCU player since 2006 -- during the Horned Frogs' 38-7 thrashing of BYU. He also made seven solo tackles and eight overall stops in the Fiesta Bowl loss to Boise State.

4. SS Tyler Sash, Iowa (6-1/210, Jr.)BUZZ: Sash is one of the nation's top playmakers. He ranked second in the Big Ten and 11th in the country in interceptions with five in 2009, when he also had 85 tackles. He is heading into his third season as a starter and has 11 career picks.

5. FS Deunta Williams, North Carolina (6-2/210, Sr.)BUZZ: Williams has made 38 consecutive starts. He ranks third in school history with 12 career interceptions. Williams was a first-team All-ACC selection last season, when he picked off six passes to rank second in the ACC. Williams also has 169 tackles in his career.

6. SS Mark Barron, Alabama (6-2/210, Jr.)BUZZ: Last season, Barron went from playing mostly on special teams to a key starter on a national title team. He led the SEC with seven interceptions last season and added 11 pass breakups. He also was second on the Tide with 92 tackles and had four quarterback hurries. He returned one of his picks for a 77-yard TD against South Carolina.

7. SS Ahmad Black, Florida (5-9/190, Sr.)BUZZ: Black lacks the prototypical size of a strong safety, but he has great instincts, good hands and can hit. He has eight picks and 129 tackles the past two seasons. He also has five pass breakups in each of the past two seasons.

8. FS Quinton Carter, Oklahoma (6-1/200, Sr.)BUZZ: Carter has good range and is a punishing hitter. He had 88 tackles, four interceptions and five pass breakups last season, his first as a full-time starter.

9. FS Will Hill, Florida (6-1/207, Jr.)BUZZ: Hill arrived amid much recruiting fanfare, and has showed glimpses of greatness in each of his first two seasons. He will be a full-time starter for the first time this fall. Hill has excellent speed and packs a punch. He has made 90 tackles in the past two seasons and also has two picks. He and Black should form the nation's best safety duo.

10. FS Robert Sands, West Virginia (6-5/221, Jr.)BUZZ: Because of his size, Sands is an imposing figure in WVU's secondary. Despite his size, Sands -- a Miami native -- runs well. He had five interceptions and eight pass breakups last season, when he also had 65 tackles. As a true freshman backup in '08, Sands made 33 tackles, showing off his ability in run support.

11. FS Brian Lainhart, Kent State (6-1/207, Sr.)BUZZ: A primo ballhawk, Lainhart's 15 career interceptions pace all returning players and are just four away from setting the school record. His seven picks in 2009 ranked fourth in the nation. Lainhart has started 32 consecutive games, registering 256 career tackles and 7.5 tackles for loss.

12. FS Wes Davis, Boston College (6-1/221, Sr.)BUZZ: An active force, Davis led BC with three picks in 2009 while ranking sixth in tackles with 46. Entering his third season as a starter, Davis was a key reserve as a true freshman in 2006 before having to redshirt in '07 because of an injury. Davis went cross-country to go to college, as he is from the San Diego area.

13. FS Jaiquawn Jarrett, Temple (6-0/197, Sr.)BUZZ: A first-team All-MAC choice in 2009, Jarrett notched 76 tackles with seven pass breakups and three interceptions. Jarrett has a nose for the ball and excels at directing traffic for one of the nation's most underrated defenses. He can run and hits a ton.

14. SS Jeron Johnson, Boise State (5-11/194, Sr.)BUZZ: A second-team All-WAC choice in 2009, the hard-hitting Johnson paced the Broncos in tackles for a second season in a row, notching 91 last fall. He also finished fourth on the club with four interceptions. Johnson has 243 career tackles with 11 tackles for loss, 19 pass breakups and seven interceptions.

15. FS Lance Mitchell, Oregon State (6-2/207, Jr.)BUZZ: He is a stellar athlete who some feel will be the Beavers' biggest defensive playmaker this fall after beginning his career as a special teams standout. Mitchell, who escaped a tough childhood in Pasadena, Calif., that was filled with violence and gangs, made 72 tackles in 2009, which ranked third on the squad.

16. SS Johnny Brown, Ole Miss (6-0/212, Sr.)BUZZ: Coach Houston Nutt says his defense will be strong and Brown is among the reasons. A steady, experienced hand, he was second among Rebels with 81 tackles in '09 and also had a pick and broke up six passes. Ole Miss needs Brown at top form to help boost a secondary with new starters at free safety and both cornerback spots.

17. FS Shiloh Keo, Idaho (5-11/216, Sr.)BUZZ: Typically, you don't want tackles made in the secondary. But if the ball gets that far, you want a sure tackler and that's Keo. An All-WAC player, Keo posted 113 tackles in '09. He intercepted three passes and broke up five, too. He also is a fine return man.

18. FS Brett Greenwood, Iowa (6-0/200, Sr.)BUZZ: Is there a better pair of safeties in the country than Tyler Sash and Greenwood? Maybe not. Greenwood received some All-Big Ten recognition a year ago after posting 55 tackles, grabbing three interceptions and breaking up seven passes. His interception in the final minute clinched a win over Michigan.

19. FS Davonte Shannon, Buffalo (6-2/205, Sr.)BUZZ: Athletic and a hard hitter, Shannon is a three-time All-MAC selection. He already is sixth on the school's career tackles list with 341. Lat season, he led the Bulls with 97 stops. He also intercepted two passes, broke up three and forced two fumbles.

20. SS Dom DeCicco, Pittsburgh (6-4/230, Sr.)BUZZ: A punishing hitter with linebacker's size and a defensive back's nose for the ball. DeCicco brings All-Big East credentials into his third season as a starter. Last season, he posted 88 tackles, with three interceptions and three pass breakups.